


Everything’ll Change | Jean Kirstein x Reader Ficlet

by tsurakofuku



Category: Shingeki no Kyojin | Attack on Titan
Genre: Cunnilingus, F/M, Ficlet, Fingerfucking, Fluff and Smut, Inspired by Music, Lemon, Multiple Sex Positions, One Shot, Oral Sex, Overstimulation, PWP, Reader-Insert, Self-Insert, Sex, Short One Shot, Smut, Vaginal Fingering
Language: English
Status: Completed
Published: 2021-03-08
Updated: 2021-03-08
Packaged: 2021-03-14 22:03:00
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 1
Words: 2,589
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29923500
Author URL: https://archiveofourown.org/users/tsurakofuku/pseuds/tsurakofuku
Summary: Valentine’s Day Runner Up: 2nd place with 373 votes! ☆ Nights in the corps are different now, but it leaves time for more physical exercise than what the commanders would approve of. Minors DNI. *I DO NOT OWN JEAN KIRSTEIN OR ATTACK ON TITAN*
Relationships: Jean Kirstein/Original Character(s), Jean Kirstein/Original Female Character(s), Jean Kirstein/Reader
Comments: 5
Kudos: 93





	Everything’ll Change | Jean Kirstein x Reader Ficlet

**Author's Note:**

> As a thank you for the passionate voting on my Valentine’s poll, the 4 runner ups will also receive a mini- fic, each inspired by a song (I know, a very cliché way to write fics). In 2nd place, we have Jean Kirstein and “Everything’ll Change” by Michl. I imagine there’s a little more privacy in the lodgings now than just the barracks - maybe singular rooms, as implied in what we see in Chapter 127? It takes place at some time during the time skip but clearly once Jean is an adult. As usual, I do not write condoms into my work. Enjoy!

Nights are different now. There’s still the ever-persistent urgency, the exhaustion that might as well be muscle memory, the warned knowledge that a jolt to action could happen any moment. A surprise training event. A stray Titan somehow, somehow. Summons from on high changing vague plans into something more concrete that demands immediate action. But for the most part, the Scouts _do_ get a full night of sleep. 

What happens between the sheets with you and Jean Kirstein disrupts this lull, leaving so much for the most part unchanged after all. The dark hours feel just as short, the burning, weak sleepiness just as present with the sunrise as years past before this life became something miraculously new. But the reasons for your aching muscles and sleepless nights have changed. 

It feels better like this.

“ _So good_ ,” you moan. 

Jean pants. The heat of his breath ghosts over your skin. The heels of his palms slide across the back of your thighs and he adjusts his grip, spreading your legs even further apart. It elicits another whimper as he lifts his head from you, a thin trail of saliva breaking from his lips when you lift your head to catch glimpses of him in the dark. 

“One of these nights,” Jean whispers, his voice almost cracking through the darkness, “someone will hear you.”

“Don’t blame _me_ ,” you say, but the sass comes out more breathless than you’d wish, and the words have no bite to them. It feels like Jean laughs, some soft breaths sharper against your skin. They get heavy again as he sinks his mouth back down.

And then it’s hard to keep that warning in mind. You clap your hand over your mouth, letting the next groan roll up through your chest but trapping the sound before it can burst from your lips. Jean keeps eating you out, fingers digging into your thighs with a strength that alone makes you shudder. Even if you were being too loud, even if curious or suspicious footfall came, he wasn’t going to let you go or give you up yet. You let your free hand down and exhale as light as you can muster it, searching for his ash-brown hair. The strands, black in the darkness, fall long between your fingers, down to the nape of his neck.

His tongue is heavy on you, moving slow but restless. He flicks up, briefly catching the taste of you and leaving you breathless and cold before dragging his tongue back down. He circles around your clit with a languid ease, upper lip brushing down against you with brief, hot motions, and up again. You writhe beneath his mouth, his fingers, pinning you down into the sheets as he moves.

“ _Fuck_ – ”

“Too loud,” Jean groans, his words making you shiver, thigh muscles straining against his persistent hold. 

“I – ” you force yourself to strangle the words into something muffled, pushing the side of your thumb into your mouth and closing your eyes. Your muscles clench and throb, begging for friction, for something more.

His splayed grip adjusts again, and Jean’s fingers drag, urging your hips to roll back into the bed as he pushes your thighs higher. One finger, then another, then his hand, drops from you, and your leg slides back down through the sheets in response.

“Keep it there,” he says, low, and thick. You lift your neck, and meet his eyes as he lifts a finger to his open mouth, drool sliding down around his lips.

When his tongue comes back, that unchoreographed slow dance through your folds again, a finger teases through them too, pressing and circling before moving down to find your entrance. You tense your thigh, pushing your knee into the wall besides the bed to keep it raised as Jean asked of you, as he slides in. You’re wet, and his saliva is cool against the heat of your skin. It’s when you feel just how achingly your body desires him, when he moves, crooks upward and rubs right against you. 

“Oh, _oh_ ” you whimper. It’s out of rhythm with his mouth as he pushes his lips and tongue against your cunt to lick up every bit of arousal he coaxes from you, but his finger presses snug and rubbing as he moves in and out with growing ease against that sensitive inner spot. He breathes, open-mouthed against your swollen folds. A pause, and with a harsh sound that can’t be stifled, spits down onto you.

“ _Fuck!_ ”

Pushing your hand, both hands now, against your mouth comes a little too late. Jean pauses in his rhythm and then you’re gasping again when a second finger strains against the first. He lets out an exhale barely louder than your own, as you clench desperately around him. 

He curls his fingers, straightening them, a beckoning motion faster and faster. Your whole body is shaking, leg contorted unceremoniously against the wall, the other so tight in his frozen grip you’re almost numb as he fucks you with his fingers. Your moans rock unsteadily out of you, a growing babble that can’t be hushed.

“Jean, _Jean,_ fuck, fuck, oh _fuck_ \- ”

You can feel your muscles twitch, your foot arching as you brush against his broad shoulders there between your legs. His tongue drags flat over you, moving up again to your clit, and his fingers curl faster and faster. Even in the darkness, everything becomes focused, the curve of your leg and the top of Jean’s head shaking in the shadows. Your hips shift into the sheets, rolling quicker than you realized you’d been moving.

Jean’s tongue slides and circles right over your clit, the curling motions coming so acutely now that it sends a heat wave down through you.

You whimper again.

“I’m – ”

“Oh, _fuck_ ” Jean says throatily, the words strained, but it’s too late to stop your orgasm as it rushes down through you in another throbbing set of ripples. You shudder, losing the rest of your sentence as you come against him, his hand slowly loosening against your thigh. One finger slides from you, even as your inner walls tighten and clench around the other. The darkness is so sharp, so bright, in this wild delirium. Your eyes roll, grey and silver spinning in the darkness and making no difference if your eyes are closed or not. If your incoherent sounds come too loud, Jean doesn’t shush you. 

“ _Oh…_ ”

Your leg slides down, back onto the mattress, as Jean pulls out of you. He doesn’t come fully away, though, with hands smearing up from your thighs, your stomach, as he sits up and braces himself against your body to lean down over you. His face is clearer for a moment, a sliver of pale light from a back window cutting down across his burning eyes, before his lips meet yours in a kiss. 

He tastes heady with your arousal on his tongue, mouth sticky against yours. Stubble scrapes against your chin when your faces collide, just rough enough, something that makes you shudder again. Jean’s lips curve, pressing a small smile into your face. He slips his tongue into your mouth. You moan into him. 

The kiss slows, Jean’s weight dipping into the bed as he draws a knee up between your collapsed legs. His breath pauses, as if he’s thinking about something. When you lift your hand to his bare, sweaty chest, his heart hammers with reverberations up through your palm.

“Can I still fuck you?” he asks, a soft whisper.

You nod, letting your nose slide down against his check as he shifts over you. “Yeah, yes.” 

You mean the blunt words, as sore and heavy as you already feel between your legs. He adjusts into a crouch with one trailing hand searching down once more. Jean leans back as his hand slide down on either side of you, face moving back into the dark haziness of the shadows. 

His fingers lift, fingertips resting and dancing over you, his breaths shaking. He’s there, his cock thick and hard against your inner leg. You lean up, unsteady on your elbows, wrapping your hand around the back of Jean’s neck and press your mouth to his again. This kiss is hungry, Jean’s mouth opening to take your lower lip between his teeth and tug as he places himself at your entrance, wet and still throbbing from your orgasm. 

“ _Fuck_ ” Jean groans, his voice sliding, and you let out a moaning “ _oh_ ” that’s a little, just a little, too loud. You sink back to the bed as Jean pushes his cock into you. Your breath catches in your throat, and one hand wanders back up to your mouth, full body trembling at the heavy, filling weight of his cock. Jean’s hands shift on the bed, sliding back up to you, as he begins to thrust. 

It’s overwhelming, the overstimulation already hitting against your sensitive folds, and you whine lowly. Your toes curl, your hips roll, muscles clenching against him. Jean’s trying to take it slow, his breath hissing through gritted teeth, but he’s been waiting too long to get inside you to keep that controlled demeanor.

“ _Shit,_ ” he lets out, and in your periphery vision one of his elbows almost buckles. “You feel… _so good_ …”

“Jean,” you whine, fingers dragging down across your chin as he moves over you, “ _fuck me_.”

Your words break into a gasp as he bends closer, forearms pushing into the bed – and _fucks you_. His motions come harder, and you rock your hips faintly in faster in rhythm to his increasingly longer thrusts. There’s some discomfort, the furrow of your forehead partly at it being too much, but the pull of his cock coming out of you, the stretch of it filling you again, brings enough pure pleasure for you to shake on him as he thrusts. You roll your eyes, and find Jean’s face over yours again. His expression is tight, strained, but his eyes are locked on you, enough to make you melt desperately for him. 

“Oh – _yeah_ ,” he groans, losing the control he’d tried to set earlier. “You feel _so good_ \- ”

All you can do is whine in response, staring up at Jean’s face. You reach up, fingers leaving your whimpering mouth to pull him close again. Your hand curves perfectly against his neck, under the long brown hair now pasted sweaty against his skin. He breathes into your open mouth, shuddering and long, and closes his lips around yours in a soft kiss. 

The kisses are short, and when he lets go, his cock slides out of you, an emptiness the closest thing to pain you’ve felt tonight. Sprawled on your elbows, you gasp up at him as he sits back, tossing his head and swiping at his forehead when his hair stays stubborn in his eyes. At this angle, the window light strikes against his shoulders, the muscles of his heaving chest, the veins in his neck and the sweat shining across his throat.

“Turn – around– ” Jean says, and you feel the sensitive soreness rush through you as you shift your hips and roll your knees to the mattress to get on all fours. Jean’s hands are locked on your hips, breathing tight and hard in your ear before you can respond, and he gives a quick, sloppy kiss to the side of your cheek before he positions himself between your bent legs.

Your knees practically go week when he slides in, and your sigh is shuddering and rises in tone as he begins to thrust into you again. You arch your back, hands straining and clutching against the sheets that slide roughly between your sweaty fingers.

“ _Ohhh…_ ”

Jean’s hands on you are hard, but the grip isn’t bruising or harsh. He’s keeping you secure, curving up under your hipbones, locked and sliding up to your waist. His next thrust in is deep, pausing and you yelp when he pauses, exhaling harsh in your ear, bottoming out inside you and your thighs tremble. 

“Sorry… one second…” Jean grunts, and when he leans his chest into your back for a moment his heart is galloping,

His grip changes and he pulls you almost upright, fingers pushing into your upper arms as he tugs them sharply behind your back with each thrust. It leaves your limbs numb, elbows bent and fingers splayed and empty, grasping for nothing. It’s erratic, wild fucking, Jean’s own groans and grunts coming louder than are probably safe for the neighbors.

“Jean,” you pant out, and he groans.

“Yes, _yes_ , fuck – ”

His words are crass but they leave you quivering. That heat teased out and burned bright by his fingers and tongue is growing again, and you try to match his speed, grinding your hips back against his in a mostly futile attempt to feed that fire. 

You’re clenching around his cock, the groans coming from you shaky as the strength flares and fades in you, the demands of your past orgasm dragging your body down no matter how hard you strain to bring that feeling back to your core where it matters. You’re still flushed and sweaty and shaking, but the overstimulation is too much for your body to reach that sweet ecstasy again. 

It still feels good enough.

“Fuck,” you whimper, moving your hips in tight circles, and Jean goes harder, faster. His thighs press against the back of yours, skin slapping messily. He lets go with one hand to cradle your waist again, and you’d slump without him, pressing your hand wildly into the mattress for support even as the ache pulls back against your other arm. Jean’s leg shifts, knee pushing against yours as he leans further into you. His strokes get tighter, shorter, and you bend your arm, lowering yourself further down to the mattress. When he lets go of your other arm, he’s fucking you into the bed, chest into your back.

“I’m gonna – ” Jean starts, a sharp groan right in your ear, and he comes, so hard that your legs quiver and some small delicious shivers shoot up in a way that’s almost pleasurable. His muscles are flexed against your body, straining to keep himself up through the pumps that shoot hot through you.

Soreness hits without distraction now when he pulls out of you, and you turn your head into the pillow and wince. Your legs are heavy, sticky, as you draw them up and shift on your side. Jean curls behind you, panting and pressing kisses against your back. His gentle hand comes dancing up again, over the curve of your thigh, your hip, the hollow of your waist, lazily moving. 

You look over your shoulder at the caress of his hand. The shadows of his eyelashes streak across his face, creating lines just as long as the stubble peppering his jaw. He sighs, deep and shuddering, suddenly so loud in the silent night

“Sleep here,” Jean whispers. He laces his fingers in yours, and you sigh too.

“You know I can’t walk out here in the morning. What if someone saw?”

“Sleep here,” Jean repeats, bringing your clasped hands to his lips and kissing them. You follow the movement. His eyes are already closed, but that faint furrow that’s begun to indent permanently into his skin is knit between his eyebrows. You kiss his fingers in return, watching them flutter, a cool light breath coming from his nostrils. Jean’s almost asleep before you can argue back, grabbing these last few dark hours before another new morning.

**Author's Note:**

> Thank you for reading! I want to make it clear I am both a JeanKasa shipper and a Jean simp, so while I don’t particularly like the “fuckboy Jean” fanon opinions because he is devoted to her, I have to lean more that way for a Reader-insert to ignore Mikasa … sorry to both her and Jean, then! Let me know what you think! :) ~ Tsura * SEE MY CARRD IN MY PROFILE FOR INFORMATION ABOUT MAKING REQUESTS *


End file.
